1. Field of the Invention
The present invention relates to a refrigerated transport vehicle provided with a refrigerator for land transportation.
This application is based on Japanese Patent Application No. Hei 11-16260, the contents of which are incorporated herein by reference.
2. Description of the Related Art
Conventional refrigerated transport vehicles are shown in FIGS. 3 and 4. In order to refrigerate an adiabatic freezing chamber 90 provided on vehicle 1, the refrigerated transport vehicle provides with a cooling system comprising an evaporator unit 10a or 10, a condenser unit 20a or 20, a compressor 5, and coolant pipes. FIG. 3 shows a refrigerated transport vehicle in which the evaporator unit 10a is arranged inside of the adiabatic freezing chamber 90, and the condenser unit 20a is arranged outside of the adiabatic freezing chamber 90 and above the vehicle 1. FIG. 4 shows a refrigerated transport vehicle in which the evaporator unit 10 is arranged outside of the adiabatic freezing chamber 90 and above the vehicle 1, and the condenser unit 20 is arranged on the bottom of the chassis 2 of the vehicle.
FIG. 5 shows that the evaporator 10 equipped with the adiabatic freezing chamber 90 as shown in FIG. 4. As shown in FIG. 5, an opening 91 for fixing the evaporator unit 10 to the adiabatic freezing chamber 90 is formed in the upper front wall of the adiabatic freezing chamber 90 in the travelling direction. The adiabatic evaporator chamber 30 is fixed to the adiabatic freezing chamber 90 so as to cover the opening 91. Metal fixtures 30d are used to fast fix the adiabatic evaporator chamber 30 to the adiabatic freezing chamber 90. The evaporator unit 10 is equipped in the upper inside wall of the adiabatic evaporator chamber 30, and maintains the inside of the adiabatic freezing chamber 90 cool. Metal fixtures 30c are used to fast fix the evaporator unit 10 to the adiabatic evaporator chamber 30. The outer and inner walls 30a of the adiabatic evaporator chamber 30 are made of reinforced plastics such as fiber-glass reinforced plastic (FRP) for light weight. Foamed synthetic resin 30b is filled between the outer and inner walls 30a to provide thermal insulation.
As shown in FIGS. 5 and 6, the evaporation unit 10 comprises a packing 11, an evaporator 12, a propeller type blower 13, an expansion valve 14, an accumulator 15, a drain water pool 16, and a drain water pipe 17. The drain water generated by the evaporator 12 is accumulated in the drain water pool 16. The drain water pool 16 is connected to the drain water pipe 17. The drain water pipe 17 passes through the adiabatic evaporator chamber 30, and discharges the drain water accumulated in the drain water pool 16 to the outside of the adiabatic freezing chamber 90.
The relationship between the evaporator unit 10, the condenser unit 20, and the compressor 5 of the cooling system will be explained with FIGS. 5 and 6. The compressor 5 provided in the engine room of the vehicle 1 is driven by the engine 6 for the driving the vehicle, via a conduction belt 7. When the compressor 5 is driven, a coolant vapor of high temperature and high pressure is generated by the compress or 5, passes through the coolant pipe 40, and reaches the condenser 21 of the condenser unit 20, while it is pressurized. Then the coolant vapor is cooled and condensed by contact with the outside air introduced by the propeller type fan 22 for the condenser. The coolant flows out of the condenser 21, passes through the receiver 23, the dryer 24, and the coolant pipe 41 between the condenser unit 20 and evaporator unit 10, and reaches the expansion valve 14 of the evaporator unit 10. Then the coolant adiabatically expands by passing through the expansion valve 14, and heat exchanges with air circulated between the adiabatic freezing chamber 90 and the evaporator 12 by the propeller type blower 13, while the coolant passes through the pipe for heat exchange. Thereby, the circulating air is cooled. The cooled circulating air is blown out as an airflow indicated by A from the air outlet 11a of the evaporator unit 10 to the inside of the adiabatic freezing chamber 90 by the propeller type blower 13 as shown in FIG. 5. The airflow A cools the inside of the adiabatic freezing chamber 90. The coolant gasified in the evaporator 12 passes through the accumulator 15, and the coolant pipe 42, and returns to the compressor 5 as shown in FIG. 6.
As explained above, the conventional refrigerated transport vehicle shown in FIG. 3 comprises the evaporator unit 10a in the adiabatic freezing chamber 90; therefore, the carrying capacity of the adiabatic freezing chamber 90 decreases. The conventional refrigerated transport vehicle shown in FIG. 4 comprises the condenser unit 20 arranged on the bottom of the chassis 2 of the vehicle; therefore a mudguard is necessary for the condenser unit 20. When a mudguard is provided, it is impossible to sufficiently employ the airflow generated by driving to cool the condenser 21. In addition, the condenser unit 20 or 20a and the evaporator unit 10 or 10a are separated in the conventional refrigerated transport vehicle; therefore, it is necessary to separately provide these units to the adiabatic freezing chamber 90. Consequently, much time is needed to fit these units. Therefore, a small and light weight cooling system has been desired.
It is therefore an object of the present invention to provide a refrigerated transport vehicle comprising a cooling system which is easily fit to the vehicle, whereby it is possible to decrease its manufacturing cost. Another object of the present invention is to provide a refrigerated transport vehicle comprising a small and light weight cooling system. Another object of the present invention is to provide a refrigerated transport vehicle in which the carrying capacity of the adiabatic freezing chamber 90 is not decreased, and the thermal efficiency is excellent.
In order to accomplish the above object, the refrigerated transport vehicle of the present invention comprises
a vehicle body;
an adiabatic freezing chamber which is provided on the vehicle body and comprises an opening;
an adiabatic evaporator chamber fixed to an outer surface of the freezing chamber so as to cover the opening and to communicate inner spaces of the freezing chamber and the evaporator chamber;
an evaporator unit provided in the inner space of the evaporator chamber for evaporating a coolant liquid and cooling the inner spaces of the freezing chamber and the evaporator chamber;
a condenser unit provided on the outer surface of the evaporator chamber for condensing a coolant vapor and discharging heat of condensation of the coolant vapor; and
a circulation system for circulating the coolant between the evaporator unit and the condenser unit.